well i've played both of these classes in both pvp and pve and i like the close combat of the knight (coupled with the force jump ability) and the force abilities of the consular, is there a mixture of both
Looking for more pve based, but with the occasional bit of PVP, i know there isn't much info on it, as while writing this was a little rushed and but busy so if needed i can add in a bit more information
Gameplay of the classes evolves as you level -- when you have more abilites to work with, you'll tend to feel less like you're just whacking your opponents repeatedly with a glowing stick. And yes, that includes force abilites. Of course, Consulars also have a melee class -- the Shadow. Or maybe you would like a non-force class. The Vanguard is melee-range, but can acquire a grapple and a jump while also retaining abilites like mortar volley (long range). *shrug*
(Excuse the font, my eyes are picky about little letters)
The Sage advanced class does focus more on force abilities such as Distortion, Project, etc. but can wade into battle with her lightsaber when called for, and has this really fancy jumping rolling kick maneuver that always makes me laugh. My Sage is specced Seer (healER, not 'healz,' get it right :P) and is impressively powerful at dps'ing while able to keep Qyzen or Iresso going strong. Conversely, the Shadow will have more powerful melee techniques while still being able to uncork Project or the channeled barrage in a pinch.
My Sentinel is only level 35 ATM and she is more a melee-range fighter than my Sage. I know the Juggernaut/Guardian both get a pretty powerful saber throw, although it is meant to be a lead-off to closing to melee with the leap. I'd say the Knight/Warrior classes are more melee oriented.
The thing to keep in mind is you cannot change advanced classes. Once you go Shadow, the ranged capabilities of the Sage are forever closed to you. And as Sensical says, each class' combat style does evolve somewhat as you grow stronger. My Powertech (mirror of the Vanguard) spent her lowest levels primarily as a ranged fighter, but now most of her strength revolves around Rocket Jump, Flamethrower and Flame Sweep, which are melee abilities, and her interrupt (Quell) only works at melee range. She can still do some powerful ranged attacks but the bulk of her moves are melee. It's the same with the Scoundrel/Operative, who can uncork some powerful blaster moves and throw explosive charges but are centered around deadly shotgun attacks (Scoundrel) or Vibroknife stabs (Operative) from behind the opponent, at melee range.
As far as choosing between Knight and Consular, I'd suggest that the Knight may have a slightly smoother and less steep learning curve, while the Consular would offer more of a challenge if you're an advanced player. But people are always asking, "which is better" and the answer to that is always the same: there is no best class, just better PLAYERS. I don't care which class I'm playing vs. what class someone else is playing, chances are they're gonna whoop my butt and then some in one on one PVP. I just don't have the reflexes or timing necessary to excel at it.